How is the rate law for for A+B = X -> C written?

Considering the following reaction:

A + B k*

k-*
X k**

C
Do I have to describe the consumption speed of X by:

  1. d(X)/dT= k*(A)(B) - k-*(X) - k**(C)
  2. d(X)/dT= k*(A)(B) - k-*(X)
or are both correct?
Serge Gomes (100572.3605@compuserve.com)

X is produced by the process you've labelled with '*' and destroyed by the processes labelled '-*' and '**'. If these are one-step processes, the net rate of change for X should be

d(X)
dt
= k*(A)(B) - k-*(X) - k**(X)

so unless k** is very small, the answer is 'none of the above'.

Author: Fred Senese senese@antoine.frostburg.edu



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